Title :
The Advanced Light Source elliptically polarizing undulator
Author :
Marks, S. ; Cortopassi, C. ; DeVries, J. ; Hoyer, E. ; Leinbach, R. ; Minamihara, Y. ; Padmore, H. ; Pipersky, P. ; Plate, D. ; Schlueter, R. ; Young, A.
Author_Institution :
Lawrence Berkeley Lab., CA, USA
Abstract :
An elliptically polarizing undulator (EPU) for the Advanced Light Source (ALS) has been designed and is currently under construction. The magnetic design is a moveable quadrant pure permanent magnet structure featuring adjustable magnets to correct phase errors and on-axis field integrals. The device is designed with a 5.0 cm period and will produce variably polarized light of any ellipticity, including pure circular and linear. The spectral range at 1.9 GeV for typical elliptical polarization with a degree of circular polarization greater than 0.8 will be from 100 eV to 1500 eV, using the first, third, and fifth harmonics. The device will be switchable between left and right circular modes at a frequency of up to 0.1 Hz. The 1.95 m long overall length will allow two such devices in a single ALS straight sector
Keywords :
electron accelerators; light polarisation; storage rings; wigglers; 1.9 GeV; 100 to 1500 eV; Advanced Light Source elliptically polarizing undulator; adjustable magnets; circular modes; circular polarization; moveable quadrant pure permanent magnet structure; on-axis field integrals; phase errors; Brightness; Error correction; Laboratories; Light sources; Magnetic separation; Magnetic switching; Optical polarization; Permanent magnets; Switches; Undulators;
Conference_Titel :
Particle Accelerator Conference, 1997. Proceedings of the 1997
Conference_Location :
Vancouver, BC
Print_ISBN :
0-7803-4376-X
DOI :
10.1109/PAC.1997.753161
